[PATCH] prevent X crash on pressing multimedia buttons, again

[Peter Hutterer]

On Thu, May 31, 2012 at 01:46:39PM +0200, Michal Suchanek wrote:
> From b824be59ebf7e9847e9e851eeb6e6c3d80c9a764 Mon Sep 17 00:00:00 2001
> From: Michal Suchanek <hramrach at gmail.com>
> Date: Wed, 23 May 2012 11:22:05 +0200
> Subject: [PATCH] Fix yet another crash in pointer event queuing.
> 
> Signed-off-by: Michal Suchanek <hramrach at gmail.com>
> ---
>  dix/getevents.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/dix/getevents.c b/dix/getevents.c
> index 9dc9617..6093799 100644
> --- a/dix/getevents.c
> +++ b/dix/getevents.c
> @@ -1574,7 +1574,7 @@ GetPointerEvents(InternalEvent *events, DeviceIntPtr pDev, int type,
>      /* Now turn the smooth-scrolling axes back into emulated button presses
>       * for legacy clients, based on the integer delta between before and now */
>      for (i = 0; i < valuator_mask_size(&mask); i++) {
> -        if (i >= pDev->valuator->numAxes)
> +        if ( !pDev->valuator || (i >= pDev->valuator->numAxes))
>              break;
>  
>          if (!valuator_mask_isset(&mask, i))
> -- 
> 1.7.10

sorry, forgot about this. merged now though I've taken the liberty of
changing the commit message.
"Fix crash for motion events from devices without valuators

A WarpPointer request may trigger a motion event on a device without
valuators. That request is ignored by GetPointerEvents but during
smooth scroll emulation we dereference dev->valuators to get the number
of axes.

Break out early if the device doesn't have valuators."
 

Cheers,
  Peter